Figure 2.

Immunoprecipitation of the plant PLA₂ activity by a monoclonal antibody raised against the purified 48-kD protein. Culture media of mouse hybridoma clones raised against the plant 48-kD protein were mixed with packed Protein A-Sepharose beads and incubate with 25 μg of partially purified PLA₂ as described in “Materials and Methods.” The resulting supernatants were assayed for the PLA₂ activity. The immunoprecipitates were subjected to 12% (w/v) SDS-PAGE as described in “Materials and Methods.” C4 and C118 mean the mouse hybridoma clones raised against the plant 48-kD protein, which were positively reactive in ELISA. Essentially identical results were obtained in three independent experiments.